Beyond Simply Environment Scaling: Designing Effective Environment Distributions for Multimodal Agent Learning

2026-08-04

AI Summary

This work addresses the limitations of existing multimodal training environments, which often lack sufficient diversity and structured difficulty progression, rendering mere increases in environment quantity ineffective for improving agent performance. To overcome this, the paper introduces two key innovations: an Ability-aware Environment Selection (AES) mechanism that dynamically selects highly diverse environments based on the agent’s current capabilities, and a Hierarchical Difficulty Curriculum (HDC) that establishes a dual-level difficulty progression—both within and across tasks. Experimental results demonstrate that the integration of AES and HDC substantially enhances learning efficiency, final performance, and cross-environment generalization, thereby surpassing conventional environment-scaling paradigms.

Abstract

Recent works train agents by constructing large-scale multimodal environment pools. However, we find that simply increasing the number of multimodal environments does not always benefit. We further analyze the limitations in current multimodal environment distributions through a series of experiments. Based on these findings, we study how to build more effective training environment distributions from two dimensions: **diversity** and **difficulty structure**. For diversity, we propose **Ability-aware Environment Selection (AES)** to obtain diverse environment sets. For difficulty structure, we propose **Hierarchical Difficulty Curriculum (HDC)**, which organizes curriculum learning through two difficulty levels: harness weakening and state-scale progression. Experiments show that AES and HDC effectively improve multimodal agent training.

Problem

• multimodal agent learning
• environment distribution
• training effectiveness
• diversity
• difficulty structure

Innovation

• multimodal agent learning
• environment distribution
• Ability-aware Environment Selection
• Hierarchical Difficulty Curriculum
• curriculum learning